1. Field of the Invention
This invention relates to an antenna array and system for minimizing the effects of jamming by nulling the received signal from the direction of the jamming signal.
2. Brief Description of the Prior Art
The power from signal jammers at the input to a global positioning system (GPS) receiver presents a severe limitation on the performance of the receiver-containing system. The prior art low cost fixed reception pattern antenna (FRPA) system provides no protection from the jammer power. Presently, the only antenna method used to reduce the power of the jamming signal at the GPS receiver is the controlled reception pattern antenna (CRPA) system. The CRPA is an adaptive antenna array driven by an algorithm and based upon feedback which minimizes the total jammer power received. In the CRPA, all of the multiple antenna elements are always active with complex electronic circuits providing the directionality or pointing of the antenna array. However, there is no known prior art relating to an intermediate level of jammer power reduction which provides jammer noise reduction approaching that of the CRPA at costs approaching that of FRPA.